TRANSDIGM INC., TRANSDIGM GROUP INCORPORATED, THE GUARANTORS NAMED HEREIN, AND THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A., as Trustee NINTH SUPPLEMENTAL INDENTURE Dated as of March 29, 2019 to Indenture Dated as of June 9, 2016 by and among...

Exhibit 4.52

TRANSDIGM INC.,

TRANSDIGM GROUP INCORPORATED,

THE GUARANTORS NAMED HEREIN,

AND

THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A.,

as Trustee

NINTH SUPPLEMENTAL INDENTURE

Dated as of March 29, 2019

to

Indenture

Dated as of June 9, 2016

by and among

TRANSDIGM INC.,

TRANSDIGM GROUP INCORPORATED,

THE GUARANTORS NAMED THEREIN,

AND

THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A.,

as Trustee

6.375% Senior Subordinated Notes due 2026

of TransDigm Inc.

This NINTH SUPPLEMENTAL INDENTURE (this “Supplemental Indenture”), dated as of March 29, 2019, is entered into by and among Xxxxxxxxx Technologies Corporation, a Delaware corporation, Souriau USA, Inc., a Delaware corporation, Esterline International Company, a Delaware corporation, Xxxxx Holding Corporation, a Delaware corporation, Xxxxx International Corporation, a Delaware corporation, Xxxxx Technology Group, Inc., a Delaware corporation, TA Aerospace Co., a California corporation, Esterline US LLC, a Delaware Limited Liability Company, CMC Electronics Aurora LLC, a Delaware Limited Liability Company, Advanced Input Devices, Inc., a Delaware corporation, Esterline Europe Company LLC, a Delaware Limited Liability Company, Esterline Georgia US LLC, a Delaware Limited Liability Company, Esterline Federal LLC, a Delaware Limited Liability Company, Angus Electronics Co., a Delaware corporation, Avista Incorporated, a Wisconsin corporation, Esterline Sensors Services Americas, Inc., a Delaware corporation, Xxxxxxxxx Technologies SGIP LLC, a Delaware Limited Liability Company, Hytek Finishes Co., a Delaware corporation, Xxxxx Corporation, a California corporation, Xxxxx Electric Co., a Delaware corporation, NMC Group Inc., a California corporation, Norwich Aero Products, Inc., a New York corporation, Palomar Products, Inc., a Delaware corporation, 00000 Xxxxxxxxx Xxxx LLC, a Delaware Limited Liability Company, Korry Electronics Co., a Delaware corporation, Memtron Technologies Co., a Delaware corporation, Sunbank Family of Companies LLC, a California Limited Liability Company, Joslyn Sunbank Company, LLC, a California Limited Liability Company, Armtec Defense Products Co., a Delaware corporation, Armtec Countermeasures Co., a Delaware corporation, Armtec Countermeasures TNO Co., a Delaware corporation, Racal Acoustics, Inc., a Delaware corporation, and Gamesman Inc., a Nevada corporation (collectively, the “Guaranteeing Subsidiaries”), TransDigm Inc., a Delaware corporation (the “Company”), TransDigm Group Incorporated, a Delaware corporation (“TD Group”), Xxxxx Rite Aerospace, Inc., a California corporation (“Xxxxx Rite”), MarathonNorco Aerospace, Inc., a Delaware corporation (“Marathon”), Champion Aerospace LLC, a Delaware limited liability company (“Champion”), Avionic Instruments LLC, a Delaware limited liability company (“Avionic”), Xxxxxx Aerospace Inc., a Delaware corporation (“Xxxxxx”), CDA InterCorp LLC, a Florida limited liability company (“CDA”), Aviation Technologies, Inc., a Delaware corporation (“ATI”), AvtechTyee, Inc., a Washington corporation (“Avtech”), Transicoil LLC, a Delaware limited liability company (“Transicoil”), AeroControlex Group, Inc., a Delaware corporation (“AeroControlex”), Xxxxx Aerospace Inc., a Delaware corporation (“Xxxxx Aerospace”), CEF Industries, LLC, a Delaware limited liability company (“CEF”), Acme Aerospace, Inc., a Delaware corporation (“Acme”), Xxxxx Aerospace, Inc., a Delaware corporation (“Xxxxx”), Semco Instruments, Inc., a Delaware corporation, (“Semco”), Xxxxxxxx Corporation, a California corporation (“Xxxxxxxx”), XxXxxxxxx Aerospace DE, Inc., a Delaware corporation (“XxXxxxxxx Aerospace DE”), XxXxxxxxx Aerospace Holdings, Inc., a Delaware corporation (“XxXxxxxxx Aerospace Holdings”), XxXxxxxxx Aerospace US LLC, a Delaware limited liability company (“XxXxxxxxx Aerospace US”), Texas Rotronics, Inc., a Texas corporation (“Rotronics”), Electromech Technologies LLC (formerly Western Sky Industries, LLC), a Delaware limited liability company (“Electromech”), Xxxxxxxxx LLC, a Delaware limited liability company (“Xxxxxxxxx”), HarcoSemco LLC, a Connecticut limited liability company (“HarcoSemco”), AmSafe Global Holdings, Inc., a Delaware corporation (“AmSafe Global”), Bridport Holdings, Inc., a Delaware corporation (“Bridport Holdings”), AmSafe, Inc., a Delaware corporation (“AmSafe Inc.”), Shield Restraint Systems, Inc. (formerly AmSafe Commercial Products, Inc.), a Delaware corporation (“Shield”), Bridport-Air Carrier, Inc., a Washington corporation (“Bridport-Air”), Bridport Erie Aviation, Inc., a Delaware corporation (“Bridport Erie”), Arkwin Industries, Inc., a New York corporation (“Arkwin”), Whippany Actuation Systems, LLC, a Delaware limited liability company (“Whippany”), Aerosonic LLC, a Delaware limited liability company (“Aerosonic”), Avionics Specialties, Inc., a Virginia corporation (“Avionics Specialties”), Airborne Global, Inc., a Delaware corporation (“Airborne Global”), Airborne Holdings, Inc., a Delaware Corporation (“Airborne Holdings”), Airborne Acquisition, Inc., a Delaware corporation (“Airborne Acquisitions”), Airborne Systems NA Inc., a Delaware corporation (“Airborne Systems NA”), Airborne Systems North America Inc., a Delaware corporation (“Airborne Systems North America”), Airborne Systems North America of CA Inc., a Delaware corporation (“Airborne Systems North America CA”), Airborne Systems North America of NJ Inc., a New Jersey corporation (“Airborne Systems North America NJ”), Telair US LLC, a Delaware limited liability company (“Telair US”), Telair International LLC, a Delaware limited liability company (“Telair International”), Pexco Aerospace, Inc., a Delaware corporation (“Pexco Aerospace”), PneuDraulics, Inc., a California corporation (“PneuDraulics”), Breeze-Eastern LLC, a Delaware limited liability company (“Breeze-Eastern”), ILC Holdings, Inc., a Delaware corporation (“ILC Holdings”), Data Device Corporation, a Delaware corporation (“DDC”), Beta Transformer Technology Corporation, a New York corporation (“Beta Corporation”), Beta Transformer Technology LLC, a Delaware limited liability company (“Beta LLC”), Young & Franklin Inc., a New York corporation (“Young & Franklin”), Tactair Fluid Controls, Inc., a New York corporation (“Tactair”), Xxxxxxx Liverpool LLC, a Delaware limited liability company (“Xxxxxxx Liverpool”), North Hills Signal Processing Corp., a Delaware corporation (“North Hills”),

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North Hills Signal Processing Overseas Corp., a Delaware corporation (“North Hills Overseas”), Kirkhill, Inc., a Delaware corporation (“Kirkhill”), TransDigm UK Holdings plc, a United Kingdom public limited company (“TD UK”), Extant Components Group Holdings, Inc., a Delaware corporation (“Extant”), Extant Components Group Intermediate, Inc., a Delaware corporation (“Extant Intermediate”), Symetrics Industries, LLC, a Florida limited liability company (“Symetrics Industries”), Symetrics Technology Group, LLC, a Florida limited liability company (“Symetrics Technology”), TEAC Aerospace Holdings, Inc., a Delaware corporation (“TEAC Holdings”), TEAC Aerospace Technologies, Inc., a Delaware corporation (“TEAC Technologies”), and Skandia, Inc., an Illinois corporation (collectively with TD Group, Xxxxx Rite, Marathon, Champion, Avionic, Xxxxxx, CDA, ATI, Avtech, Transicoil, AeroControlex, Xxxxx Aerospace, CEF, Acme, Xxxxx, Semco, Xxxxxxxx, XxXxxxxxx Aerospace DE, XxXxxxxxx Aerospace Holdings, XxXxxxxxx Aerospace US, Rotronics, Electromech, Xxxxxxxxx, HarcoSemco, AmSafe Global, Bridport Holdings, AmSafe Inc., Shield, Bridport-Air, Bridport Erie, Arkwin, Whippany, Aerosonic, Avionics Specialties, Airborne Global, Airborne Holdings, Airborne Acquisitions, Airborne Systems NA, Airborne Systems North America, Airborne Systems North America CA, Airborne Systems North America NJ, Telair US, Telair International, Pexco Aerospace, PneuDraulics, Breeze-Eastern, ILC Holdings, DDC, Beta Corporation, Beta LLC, Young & Franklin, Tactair, Xxxxxxx Liverpool, North Hills, North Hills Overseas, Kirkhill, TD UK, Extant, Extant Intermediate, Symetrics Industries, Symetrics Technology, TEAC Holdings and TEAC Technologies, the “Existing Guarantors”), and The Bank of New York Mellon Trust Company, N.A., as trustee (the “Trustee”) under the Indenture referred to below.

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WITNESSETH:

WHEREAS, the Company and the Existing Guarantors have heretofore executed and delivered to the Trustee an indenture, dated as of June 9, 2016 (as supplemented by the First Supplemental Indenture thereto, dated as of July 8, 2016, the Second Supplemental Indenture thereto, dated as of October 28, 2016, the Third Supplemental Indenture thereto, dated as of March 31, 2017, the Fourth Supplemental Indenture thereto, dated as of May 9, 2017, the Fifth Supplemental Indenture thereto, dated March 30, 2018, the Sixth Supplemental Indenture thereto, dated as of May 8, 2018, the Seventh Supplemental Indenture thereto, dated as of May 22, 2018, and the Eighth Supplemental Indenture thereto, dated as of July 31, 2018, the “Indenture”), providing for the issuance by the Company of 6.375% Senior Subordinated Notes due 2026 (the “Notes”) and the guarantees thereof by each of the Existing Guarantors;

WHEREAS, the Indenture provides that under certain circumstances described therein, newly created or acquired Domestic Restricted Subsidiaries shall execute and deliver to the Trustee a supplemental indenture to the Indenture providing for a senior subordinated guarantee of payment of the Notes by such Domestic Restricted Subsidiaries (the “Guarantee”);

WHEREAS, all things necessary to make this Supplemental Indenture the legal, valid and binding obligation of the Company, the Existing Guarantors and the Guaranteeing Subsidiaries have been done; and

WHEREAS, pursuant to Section 9.01(g) of the Indenture, the Trustee is authorized to execute and deliver this Supplemental Indenture without the consent of the Holders of the Notes.

NOW, THEREFORE, in consideration of the foregoing and for other good and valuable consideration, the receipt of which is hereby acknowledged, the Guaranteeing Subsidiaries covenant and agree for the equal and ratable benefit of the Holders of the Notes as follows:

1. CAPITALIZED TERMS. Capitalized terms used herein without definition shall have the meanings assigned to them in the Indenture.

2. GUARANTEE, ETC. The Guaranteeing Subsidiaries hereby agree that from and after the date hereof they shall be Guarantors under the Indenture and be bound by the terms thereof applicable to Guarantors and shall be entitled to all of the rights and subject to all the obligations of a Guarantor thereunder.

3. RATIFICATION OF INDENTURE; SUPPLEMENTAL INDENTURE PART OF INDENTURE. The Indenture is in all respects ratified and confirmed and all the terms, conditions and provisions thereof shall remain in full force and effect. This Supplemental Indenture shall form a part of the Indenture for all purposes, and every holder of Notes heretofore or hereafter authenticated and delivered shall be bound hereby.

4. EXECUTION AND DELIVERY. The Guaranteeing Subsidiaries agree that the Guarantee granted by them pursuant to the terms hereof shall remain in full force and effect notwithstanding any failure to endorse on each Note a notation of such Guarantee.

5. NO RECOURSE AGAINST OTHERS. No past, present or future director, officer, employee, incorporator, stockholder or agent of the Guaranteeing Subsidiaries (or any successor entity) (other than the Company or the Existing Guarantors), as such, shall have any liability for any obligations of the Company, TD Group, the Guaranteeing Subsidiaries or any other Guarantor under the Notes, any Guarantee, the Indenture or this Supplemental Indenture or for any claim based on, in respect of, or by reason of, such obligations or their creation. Each Holder of the Notes by accepting a Note waives and releases all such liability. The waiver and release are part of the consideration for issuance of the Notes.

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6. NEW YORK LAW TO GOVERN. THE INTERNAL LAW OF THE STATE OF NEW YORK SHALL GOVERN AND BE USED TO CONSTRUE THIS SUPPLEMENTAL INDENTURE AND THE GUARANTEE GRANTED HEREUNDER WITHOUT GIVING EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT THAT THE APPLICATION OF THE LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY.

7. COUNTERPART ORIGINALS. The parties may sign any number of copies of this Supplemental Indenture. Each signed copy shall be an original, but all of them together represent the same agreement.

8. EFFECT OF HEADINGS. The Section headings have been inserted for convenience of reference only, are not to be considered part of this Supplemental Indenture and shall in no way modify or restrict any of the terms or provisions hereof.

9. THE TRUSTEE. The Trustee shall not be responsible in any manner whatsoever for or in respect of the validity or sufficiency of this Supplemental Indenture or for or in respect of the recitals contained herein, all of which recitals are made solely by the Guaranteeing Subsidiaries, the Existing Guarantors and the Company.

[Signature page follows.]

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IN WITNESS WHEREOF, the parties hereto have caused this Supplemental Indenture to be duly executed as of the date hereof.

SOURIAU USA, INC.

XXXXX INTERNATIONAL CORPORATION

TA AEROSPACE CO.

CMC ELECTRONICS AURORA LLC

ADVANCED INPUT DEVICES, INC.

ESTERLINE GEORGIA US LLC

ESTERLINE FEDERAL LLC

AVISTA, INCORPORATED

ESTERLINE SENSORS SERVICES AMERICAS, INC.

HYTEK FINISHES CO.

XXXXX ELECTRIC CO.

NMC GROUP, INC.

NORWICH AERO PRODUCTS, INC.

PALOMAR PRODUCTS, INC.

KORRY ELECTRONICS CO.

MEMTRON TECHNOLOGIES CO.

JOSLYN SUNBANK COMPANY, LLC

ARMTEC DEFENSE PRODUCTS CO.

ARMTEC COUNTERMEASURES CO.

ARMTEC COUNTERMEASURES TNO CO.

GAMESMAN INC.

ESTERLINE INTERNATIONAL COMPANY

XXXXX HOLDING CORPORATION

XXXXX TECHNOLOGY GROUP, INC.

XXXXXXXXX US LLC

ESTERLINE EUROPE COMPANY LLC

ANGUS ELECTRONICS CO.

XXXXX CORPORATION

SUNBANK FAMILY OF COMPANIES, LLC

RACAL ACOUSTICS, INC.

XXXXXXXXX TECHNOLOGIES CORPORATION
00000 XXXXXXXXX XXXX LLC

By: Xxxxxxxxx Technologies Corporation, as its sole member

XXXXXXXXX TECHNOLOGIES SGIP LLC

By: Xxxxxxxxx Technologies Corporation, as its sole member

By:		/s/ Xxxxxxxx X. Xxxxxxxx
Name:		Xxxxxxxx X. Xxxxxxxx
Title:		Treasurer
TRANSDIGM INC.
By:		/s/ Xxxxxxx X. Xxxxxx
Name:		Xxxxxxx X. Xxxxxx
Title		Chief Financial Officer
TRANSDIGM GROUP INCORPORATED
By:		/s/ Xxxxxxx X. Xxxxxx
Name:		Xxxxxxx X. Xxxxxx
Title		Chief Financial Officer

[Signature page to the Ninth Supplemental Indenture – 2026 Notes]

ACME AEROSPACE, INC.

XXXXX RITE AEROSPACE, INC.

AEROCONTROLEX GROUP, INC.

AIRBORNE ACQUISITION, INC.

AIRBORNE GLOBAL, INC.

AIRBORNE HOLDINGS, INC.

AIRBORNE SYSTEMS NA INC.

AIRBORNE SYSTEMS NORTH AMERICA INC.

AIRBORNE SYSTEMS NORTH AMERICA OF CA INC.

AMSAFE GLOBAL HOLDINGS, INC.

AMSAFE, INC.

ARKWIN INDUSTRIES, INC.

AVIATION TECHNOLOGIES, INC.

AVIONICS SPECIALTIES, INC.

AVTECHTYEE, INC.

BETA TRANSFORMER TECHNOLOGY CORPORATION

BETA TRANSFORMER TECHNOLOGY LLC

By: Beta Transformer Technology Corporation, as its sole member

BRIDPORT HOLDINGS, INC.

BRIDPORT-AIR CARRIER, INC.

XXXXX AEROSPACE INC.

DATA DEVICE CORPORATION

XXXXX AEROSPACE, INC.

ELECTROMECH TECHNOLOGIES LLC

By: XxXxxxxxx Aerospace US LLC, as its sole member

By: XxXxxxxxx Aerospace DE, Inc., as its sole member

EXTANT COMPONENTS GROUP HOLDINGS, INC.

EXTANT COMPONENTS GROUP INTERMEDIATE, INC.

XXXXXXXX CORPORATION

ILC HOLDINGS, INC.

XXXXXXX LIVERPOOL LLC

By: Young & Franklin Inc., as its sole member

KIRKHILL INC.

MARATHONNORCO AEROSPACE, INC.

XXXXXXXXX AEROSPACE DE, INC.

XXXXXXXXX AEROSPACE HOLDINGS, INC.

XXXXXXXXX AEROSPACE US LLC

By: XxXxxxxxx Aerospace DE, Inc., as its sole member

NORTH HILLS SIGNAL PROCESSING CORP.

NORTH HILLS SIGNAL PROCESSING OVERSEAS CORP.

PEXCO AEROSPACE, INC.

PNEUDRAULICS, INC.

SEMCO INSTRUMENTS, INC.

SHIELD RESTRAINT SYSTEMS, INC.

SKANDIA, INC.

XXXXXX AEROSPACE INC.

SYMETRICS INDUSTRIES, LLC

By: Symetrics Technology Group, LLC, as its sole member

By: Extant Components Group Intermediate, Inc., as its sole member

SYMETRICS TECHNOLOGY GROUP, LLC

By: Extant Components Group Intermediate, Inc., as its sole member

TACTAIR FLUID CONTROLS, INC.

[Signature page to the Ninth Supplemental Indenture – 2026 Notes]

TEAC AEROSPACE HOLDINGS, INC.

TEAC AEROSPACE TECHNOLOGIES, INC.

TEXAS ROTRONICS, INC.

TRANSICOIL LLC

By: Aviation Technologies, Inc., as its sole member

YOUNG & FRANKLIN INC.

By:		/s/ Xxxxxxxx X. Xxxxxxxx
Name:		Xxxxxxxx X. Xxxxxxxx
Title:		Treasurer

AEROSONIC LLC
AVIONIC INSTRUMENTS LLC
BREEZE-EASTERN LLC
CDA INTERCORP LLC
CEF INDUSTRIES, LLC
CHAMPION AEROSPACE LLC
HARCOSEMCO LLC
XXXXXXXXX LLC
TELAIR US LLC
TELAIR INTERNATIONAL LLC
By: Telair US LLC, as its sole member
WHIPPANY ACTUATION SYSTEMS, LLC
Each By: TransDigm Inc., as its sole member
By:		/s/ Xxxxxxx X. Xxxxxx
Name:		Xxxxxxx X. Xxxxxx
Title:		Chief Financial Officer
AIRBORNE SYSTEMS NORTH AMERICA OF NJ INC.
By:		/s/ Xxxxxxx X. Xxxxxx
Name:		Xxxxxxx X. Xxxxxx
Title:		Chairman of the Board and Chief Executive Officer
BRIDPORT ERIE AVIATION, INC.
By:		/s/ Xxxxxxxx X. Xxxxxxxx
Name:		Xxxxxxxx X. Xxxxxxxx
Title:		Chairman of the Board and President
TRANSDIGM UK HOLDINGS PLC
By:		/s/ Xxxxxxxx X. Xxxxxxxx
Name:		Xxxxxxxx X. Xxxxxxxx
Title:		Director

[Signature page to the Ninth Supplemental Indenture – 2026 Notes]

THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A., AS TRUSTEE
By:		/s/ X. Xxxxxx
Name:		X. XXXXXX
Title:		VICE PRESIDENT

[Signature page to the Ninth Supplemental Indenture – 2026 Notes]